I tested speeds on my comcast accounts over the years, and I noticed something hinky.If I use well known speed testers, I get about what comcast says I should.On the other hand, if I use more obscure testers, the speeds are a LOT lower, but are consistent between different tests.

So I tried the more well known tests again, but I obfuscated them so comcast wouldn't know what I was doing.Guess what. The speeds went way down to the same thing the more obscure tests were saying.

That seems to indicate that comcast is actually giving you a much lower speed than advertised, but try to protect themselves from law suits by saying 'up to' on their rates, but will temporarily boost you to what you paid for if they detect you trying to run a test on them. (That's pretty much standard practice for a con man trying to prevent you from learning about the con.)

My understanding was that Comcast capped my usage (I have a "Blast Plus" account) at 250GB/month. Seems to reset every month at 0000Z on the first.

I monitor my own usage fairly carefully, I think last month I was a bit over 300GB. But: Comcast announced [comcast.com] that they are temporarily suspending enforcement of their cap - as of May, 2012. They have indicated that they are going to replace the cap with "new approaches", but there doesn't seem to be any mention of this since that date.

There's clearly tension between the cost of the plant necessary to support large users of data and the profit of the corporation. Without diving into that debate, I will relate what I've heard in discussions with a few other technically-oriented customers: they really didn't engineer their network to support any significant level of symmetric usage (it's designed for some multiples of download traffic over upload traffic), and the whole question of traffic shaping was a response to an actual "fear" that their network would be trashed by BitTorrent users.

I don't know whether that's actually true. But I do know that ultimately, all resources on the Internet are shared, and that without sufficient bandwidth there is lots of potential that won't be attained. I have some level of sympathy for the idea that someone may have to be throttled to keep costs for usage roughly equal for all customers of a particular class, or that pricing might have to be "reasonably" adjusted based on usage - especially peak usage (I do offsite vaulting exclusively between 0100 and 0500 local time).

I'd hope that Comcast and the other ISPs realize that the only way they are going to be able to make their business case to their customers if they operate transparently - and I know that's not the initial strategy for any large corporation. I don't think most people have an issue with paying "reasonable" fees - but, again, in the telecomm/service industry in general, that's generally how things are priced.

They are going to have to figure out how to make some profits on what anyone reading this already considers a "utility" - they sure aren't getting revenue from my pageviews of the ads on their home page. However, I've heard too many stories of how Internet connectivity delivered as a pure utility (especially by non-profits such as municipal governments) provides better service, higher bandwidth (sic) and lower costs than investor-owned corporations; if I could vote (if it were practical in my section of Boston) for that, as a public good, it'd make this discussion go away.

It's pretty well established that Comcast cheats on speed tests. They have that feature where they boost the first bit of a download to a much higher rate, and that tends to have bandwidth testers showing an unreasonably rosy picture of the situation. I guess that might not technically be cheating, but it's something that people should realize, you need a longer test to determine what you're really getting as the first bit will always be substantially faster.

A great example I have of that on my ISP is that a friend of mine had a large file he wanted to download from his webserver. His transfer was taking forever, so I jokingly suggested that he copy it to a directory called speedtest and download it with HTTP. He does and BAM the file screams down. At the same time with the same file, just with different paths and file names (he just shortened it to save the effort in typing the name), he had the original transfer at 50 KB/s or so and the new one at 2 MB/s! I've done that many times to great success.

Imagine if the power companies decided to cap its users. "Sorry but only 200kw/hr per month. Any higher and we either turn you off or throttle your usage by opening a circuit breaker if you use more than 2kw." People would form lynch mobs. And its no secret that power grids are already taxed in many parts of the US. How about if gas companies told you: you have 1000 cubic feet of gas for this month. its either heat your home or cook or have hot water, you cant have all three. The ISP's can happily cry about how their infrastructure is overloaded by file sharing and Netflix yet do nothing to actually invest in more capacity. They instead pander to the share holders to make sure this quarters profits are up, customer be dammed. Yes people can happily survive without the internet but people could also survive without gas and electric and have done so for thousands of years. We have gotten to a point where the internet is starting to become very important in our lives and one day it may be difficult to live without it.

Just a tidbit about power throttling:Back in high school shop class (I took commercial/residential electrical installation). there was this metal collar that fit onto a meter pan between the pan and meter. It had two 20 amp circuit breakers sticking out of it (the push to reset type). The idea was if someone was on a social assistance program and couldn't afford power, this collar was installed and gave just enough power to run some lights, TV, refrigerator, a fan and *maybe* a single AC unit. This way the person received free subsidized power that they couldn't abuse without modifying any building wiring. If they used too much and tripped the breaker all they needed to do was go to the meter and reset the breaker.